<h3>Return Book Form</h3>
  <form action="ReturnBook" method="post" style="width:300px">
  <div class="form-group">
    <label for="callno1">Callno</label>
    <input type="text" class="form-control" name="callno" id="callno1" placeholder="Callno"/>
  </div>
  <div class="form-group">
    <label for="studentid1">Student Id</label>
    <input type="text" class="form-control" name="studentid" id="studentid1" placeholder="StudentId"/>
  </div>
  <button type="submit" class="btn btn-primary">Return Book</button>
</form>